There are many ways to specify a location of an object. For example, within a building, an object may be specified as being in a particular room on a certain floor of the building. Within a retail store, an object may be specified as being on a particular shelf of a designated aisle. More generally, a location of an object may be specified with reference to designated landmarks. In particular, for example, Global System for Mobile Communications (GSM) triangulation may be performed with respect to cell (telephone) towers, so as to locate a particular cell phone.
Even more generally, location may be specified with respect to the Earth's surface, using, for example, coordinates specified by a latitude, longitude, and altitude of the object. In particular, the Global Positioning System (GPS) uses a number of Earth-orbiting satellites to determine a position of a GPS transceiver that exchanges signals with the satellites.
Such location information may or may not be useful, depending on the circumstances of a user of the information. In the case of the retail store, for example, a user who is unfamiliar with a layout of the store may find aisle/shelf information to be unhelpful. Even if the user is familiar with the store layout, the user may be unable to communicate the aisle/shelf information to another user in an effective manner. Somewhat similarly, latitude, longitude, and altitude information of a GPS transceiver may be required to be expressed with respect to a map of a city in which the GPS transceiver is currently located, in order for a user of the transceiver to navigate through the city.
Such issues, related to the sharing and use of location information, may generally be magnified when large numbers of objects, frequent instances of location-gathering, and/or large numbers of users are involved. Such users may have different needs or expectations with respect to, for example, an expression, precision, transmission, storage, or use of the location information. Moreover, the needs or expectations of each user may vary according to particular types of objects, or may vary even for a single object, depending on the circumstance of the object.